不同光质LED暗期补光对水培切割再生生菜生长和生理的影响

Effect of different R/B LED in dark period on the growth and physiology of hydroponic regeneration lettuce

采用耐切割叶用莴苣品种‘奶油生菜’为试材,以海南夏季锯齿型温室内自然光照和光周期为对照,利用LED精量调制红蓝光比例分别为R/B=4、8、10,对水培生菜切割一茬后的再生苗进行夜间延时补光,探究不同光质LED暗期补光对水培切割再生生菜生长和生理的影响。结果表明:R/B=8、10两个处理的再生生菜采收时单株地上部鲜质量达到对照的2.36、2.13倍,随着LED红蓝复合补光光源红光比例的增加,生菜地上部鲜质量和可溶性蛋白含量呈现先增加后减小、可溶性糖含量持续增加的趋势。光合色素以R/B=10的含量最高,叶绿素荧光指标R/B=8、10处理高于CK和R/B=4处理。R/B=8处理的脯氨酸、SOD酶含量极显著或显著高于其他3个处理,EC值、MDA含量表现出R/B=4处理显著低于CK。综合各指标来看,对水培生菜再生苗进行暗期延时补光处理时,R/B=8是最优的光质配比。

In order to find out the influence of different R/B LED in dark period on the growth and physiology of hydroponic regeneration lettuce.‘Butter lettuce' was taken as experimental material, three treatments(R/B=4, 8, 10) were carried out and the treatment of that in natural light in Zigzag greenhouse was set to be CK. The results showed that the Top FW per plant of regeneration lettuce in treatment of R/B =8, 10 were the 2.36, 2.13 times as high as that of CK. With the increase of proportion of red light, the Top FW per plant and soluble protein of regeneration lettuce increased first and then decreased, while the soluble sugar of that continuously increased. The photosynthetic pigments of the R/B =10 were the highest, chlorophyll fluorescence of R/B =8, 10 were higher than those of CK and R/B =4. The proline content and SOD activity of R/B =8 were remarkably higher than those of other three treatments. EC value and MDA content of R/B =4 were lower than those of CK. In conclusion, the treatment of R/B=8 showed the optimal proportion of light and quality.